Department of Energy Argonne National Laboratory Office of Science NEWTON's Homepage NEWTON's Homepage
NEWTON, Ask A Scientist!
NEWTON Home Page NEWTON Teachers Visit Our Archives Ask A Question How To Ask A Question Question of the Week Our Expert Scientists Volunteer at NEWTON! Frequently Asked Questions Referencing NEWTON About NEWTON About Ask A Scientist Education At Argonne Host Rock for Gold
Name: Tim
Status: Student
Grade: 4-5
Location: N/A
Country: Australia
Date: May 2007


Question:
Can gold be found in any other host rock other than quartz?



Replies:
Gold is often brought into rocks dissolved in hot magmatic waters. As such it can be deposited in any rock that allows the passage of these hot waters through cracks and or primary porosity. As a result you can get what are known as disseminated gold ores where the gold is so fine you cannot see it with the naked eye of even a low power microscope.

In other cases, gold bearing rock may be eroded and the gold re-deposited in other rock types. Again, this may lead to a very low grade of ore, but one that is still economically useable.

Gold can also be mixed with other metallic ores in very small amounts. For many years, New Jersey Lead and Zinc Co., recovered the gold present in their lead/zinc ore by scraping and refining the metallic scale in the furnaces and retorts. The gold paid their expenses and the lead and zinc were pure profit. As a result, they continued to refine ore even in times of poor lead and zinc prices.

As the old saying goes, "Gold is where (and in what rock) you find it".

Bob Avakian
OSU-Okmulgee


Gold forms few, if any, chemical compounds that are stable in a geological environment. I do not know of any, but there could be. Consequently, metallic gold finds itself in an environment that is most plentiful and non-reactive. Quartz fills those two conditions. I suspect that is why metallic gold is usually found in a quartz matrix.

Vince Calder


From the famous PBS series "The Making of the Continent" (North America), it was given that if you find "greenstone or more particularly greenschist" you are likely to find gold or silver.

Greenstone and Greenschist can be found at the following site:

http://en.wikipedia.org/wiki/Greenstone_belt

http://en.wikipedia.org/wiki/Greenstone

http://en.wikipedia.org/wiki/Greenschist

Steve Sample



Click here to return to the Environmental and Earth Science Archives

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (help@newton.dep.anl.gov), or at Argonne's Educational Programs

NEWTON AND ASK A SCIENTIST
Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012
Weclome To Newton

Argonne National Laboratory